Printing mechanisms



Nov. 19, 1957 F. H. FOWLER, JR

PRINTING MECHANISMS 3 Sheets-Sheet 1 Filed Oct. 13, 1955 INVENTOR Nov. 19, 1957 F. H. FOWLER, JR 2,813,480

PRINTING MECHANISMS Filed Oct. 18, 1955 3 SheetsSheet 2 INVENTORL FAWA/KL/N H. Fax 4% ATTORNEY 1957 F. H. FOWLER, JR

PRINTING MECHANISMS 3 Sheets-Sheet 3 Filed Oct. 18, 1955 @EEEEEEEE EEEEEEEEEE ESE 5E ESE EE Emm Ewm EE-E EE E EEE EE-E WIWIIQ wE W Ew E EE wmWTEE wmTl TEE INVENTOR wmwubk 3.520% N WE T, y a M.

United States PatentOfiice 2,813,480 PRINTING MECHANISMS Franklin H. Fowler, Jr., Haddonfield, N. J. -Application October 18, 1955, Serial No. 541,187

Claims. (Cl. 101-93 The present invention relates to printing mechanisms and more particularly to a printing mechanism for printing on a continuously moving web of a print receiving medium.

It is a primary object of the present invention to provide a printing mechanism for printing characters on a continuously moving web of a print receiving medium such as a Web of paper. The term character is employed herein to designate any form of printed token or design which it may be desired to apply to a print receiving medium.

' It is another object of the present invention to provide a printing mechanism for printing characters on a continuously moving web of a print receiving medium, wherein the characters are applied to the medium by a plurality of character printing members disposed in a row parallel to the direction of movement of the moving web.

Another object of the present invention is to provide a printing mechanism for printing characters on a continuously moving web of print receiving material. The characters are applied to the web by a plurality of character printing members arranged in a row parallel to the direction of the movement of the Web through the printing mechanism. In an embodiment of the invention employing a single row of character printing members, it is possible to print only a single line of characters on the web on each pass of the web through the printing mechanism. Additional lines of characters may be printed on the web during each pass by providing additional rows of character printing members arranged serially along the path of travel of the web and displaced transversely to the direction of travel of the web by a distance equal to the distance between lines of characters.

Still another object of the present invention is to provide a plurality of character printing members arranged in a row parallel to the direction of movement of a continuously moving web of a medium upon which it is desired to apply a plurality of various characters. Actuation of the character printing members to apply designs to the moving web is under the control of an information comparison system. Each character printing member is represented in the information comparison system by a 1 different unit of coded control information and various characters to be applied to the moving Web during any printing sequence are represented by units of coded data information. Each unit of coded data information is sequentially compared with each unit of coded control information and upon detection of an identity between the coding of the data information and the control information the character printing member represented by the data information is actuated. The comparison of each unit of the data information with each unit of the control information is synchronized with the movement of the web through the printing mechanism so that the area of the web that is to receive a particular character is adjacent the character printing member for printing Patented Nov. 19,1957

that character when the comparison between the units of data and control information representing that character is effected.

The present invention is particularly useful as a high speed typewriter. The typewriter is provided with eightyfour character printing members, this number being required since a shift mechanism is not provided and as a result separatemembers are required for the capital and lower case letters of each letter of the alphabet.

In a first specific embodiment of a typewriter of the present invention, the units of data information are arranged on a perforated tape, each unit of data information being disposed in a single column perpendicular to the length of the tape. A three-out-of-nine code is employed; that is, each column of the tape is provided with nine locations for perforations, only three of which are employed for each unit of code. The three-out-of-nine code provides 84 different arrangements of the three perforations in each column, and, therefore, provides a separate code designation for each of the 84 different character applying members of the typewriter.

The three-out-of-nine code is preferred since this code provides exactly 84 code variations. However, it is to be understood that the present invention is not limited to the use of this code, there being other codes Well known in the art, such as the binary code, which may be employed.

Actuation of the character printing members is under the control of a photoelectric sensing mechanism com prising a perforated mask having a plurality of units of control information in the form of columns of coded perforations, each column of perforations being indicative of one of the character applying members. The columns of the mask are arranged along the path of the travel of the tape so that each column on the tape is sequentially presented to each column of the mask. Each column of perforations of the mask contains six perforations which are arranged to be complementary to the three perforations on the tape. Light is directed through the perforated tape and then through the perforated mask and-the light passing through each corresponding column of the tape and the mask is sensed by a separate photoelectric cell. Since the perforations of the tape and mask are complementary an identity between the codes on the tape and mask is indicated by the absence of light impinging upon the photoelectric cell. The output voltage from the photo-cell is connected to one input terminal of a coincidence gate, the other input terminal of which is connected to a source of synchronizing voltage pulses. Synchronizing voltage pulses are necessary since as the tape moves over the mask, the unperforated areas of the tape between the columns of perforations pass over the perforated areas of the mask and prevent light from reaching any of the photocells. Therefore, synchronizing pulses are applied to the coincidence gates only during those intervals when the columns of perforations of the tape are disposed adjacent to the columns of perforations on the mask. The synchronizing signals may be derived from a tenth perforation in each column of the tape. Alternatively, and preferably, a mechanical switching arrangement synchronizedwith the perforated tape drive mechanism may be employed to generate the synchronizing signals.

Upon coincidence of output voltages from the photocell and the synchronizing source, the coincidence gate developes an output voltage which energizes a solenoid which in turn actuates a character applying member to print on the moving web.

Progression of the tape through the sensing mechanism and of the web through the printing mechanism is so syn? pchronized that the columnof perforations in the tape,

3 indicating the character to be applied to the particular area of the web, is being compared at a given instant with the row of perforations in the mask representing the character carrying member adjacent which the particular area of theweb is disposed atthat moment. Therefore, when an identity between the perforations on the tape and the mask is detected the area of the web which is to receive the character designated by these perforations is] adjacent the character applying member actuated by the sensing mechanism.

The perforated tape-perforated mask arrangement described aboveis exemplary. of a number of different. sensing arrangements employing similar techniques. Thus a magnetic tape-magnetic head arrangement may be employed. Insuch an arrangement armagnetic tape is providedwith ninev recording channels and the units of data information are recorded in the channels in columns'perpendicular to the channels. A three-out-of-nine code may again be employed but data information in the form of magnetic indications is applied to six channels of, the tape in each column so that only three magnetic readingrheads arranged in columns parallel to, the columns of data information on the tape must be employed to provide each unit, of control information.v Again, complementary codes are employed so that the absence of an input signal from the three magnetic reading heads indicates an identity of codes. Synchronizing signals may be. recorded in a tenth channel'of the tape or a mechanicalswitch system may be employed.

In addition to punched tape and magnetic tape systems, photographic film and magnetic drum systems may be employed; The photographic film would be employed in a system identical to the perforated tape system, the film-being generally opaque and having transparent areas corresponding to the perforations in the tape. The magnetic drum system would be identical to the delay line system to be described except that-the units of data information would be stored on a magnetic drum instead of in a delay line.

Other similar arrangements may be employed which utilize electromechanical coding and sensing systems, or wholly mechanical coding and sensing systems. In an electromechanical system which may be-employed in the present invention each unit ofcontrol information is represented by a plurality of normally'open' switches arranged in-acolumnperpendicular to the path of travel of the web, the physicalpositioning of the switches in each column determining the code; A three-out-of-nine code may again be employed so that the three switches may be arranged in nine different rows. The switches are selectively closed by cams arranged in gr-oups'of nine, each group of nine being positioned on a bar which is perpendicular to the path of travelof the web. The bars are employed as crossmembers inan endless belt, the movement' of the belt being synchronized with the movement of the web so that each bar with its associated cams is sequentially presented to each group of switches as each area of the web is sequentially presented to each character applying member. Each cam. of a group is arranged in a difierent one of the nine rows and has two positions, one in which it will close any switch to which it is presented and a second position in which it does not affect the switches to which it, is presented. The position of each cam in a row is controlled by a solenoid disposed along the path of travel of the cams in a row, as each cam moves past its associated solenoid. If the cams on a given bar are positioned such that, they close all of the switches in a given column, a solenoid associated with that given column is energized and actu-atesan associated character printing member. A similar arrangement for sorting perforated cards is. described in an article by Jacob Robinow entitled Cams as binary numbers dial card sorting. stations, Product Engineering, January. 1954, pages 150-153;

In a wholly mechanical arrangement, the'character' applying members may be positioned on permutation bars, which bars are oscillated vertically by a mechanically resonate system of which the bars form a part. The bars are arranged above the character receiving web and printing occurs when a bar oscillates downwardly through its maximum amplitude. A plurality of cam carrying bars form the cross members of an endless belt, the bars passing between the permutation bars and the web of character receiving material. Each permutation bar is provided with a plurality of teeth, the position of the teeth on each permutation bar being different from the position of the teeth on each; of the other permutation bars. The cams carried on the links have two positions. If any cam on a given link is positioned so that it lies under a tooth on the permutation bar, the bar is physically prevented from oscillating through its maximum downward amplitude and, therefore, printing does not occur. On the other hand, when all of the cams on a particular link are positioned so that none of them lies under any of the teeth of thepermutati'on bar, the bar oscillates through its maximum amplitude and printing occurs.

It is, therefore, another object of the present invention to employ a perforated tape, and photoelectric sensing mechanism in a typewriter for actuating selected members of, a plurality of character applying members disposed in a row parallel to the direction of movement of a web of paper which moves continuously through the typewriter.

Yet another object of the present invention is to provide a printing mechanism employing a comparison mechanism for detecting identity between coded data information arranged on a movable carrier and coded control information arranged serially along the path of movement of the movable carrier wherein the movement of the movable carrier past the control information is synchronized with the movement of a web of a print receiving mechanism past a plurality of character applying members arranged in a row parallel to the direction of movement of the'web and wherein each character applying'member is represented by a different unit of control information.

In each of the arrangements thus far described the units of control information are represented by mechanical members. Thus, in the perforated tape embodiment, perforation in a mask represent the control information, in the magnetic tape or drum arrangement, magnetic heads are utilized while inthe electro-mechanical and wholly mechanical arrangements electric switches and permutation bars are employed, respectively. However, it is not intended. to limit the present invention to such systems.

In another embodiment of the present invention the units of control information are represented by coded voltage pulses, the units of control informationprogressing serially through an. electrical delay line having a recirculation circuit. The recirculation circuit is provided by connecting an output terminal of the electrical delay line to an input terminal of thedelay line. The units of data information are also represented. by coded voltage pulses which progress serially'through a. second electrical delay. line having a recirculation. circuit. The recirculation circuit, of the second delay line includes a gating circuit arranged to permit the insertion of new data information. The time delay of both delay lines is chosen such that each unit of data, information is compared with a unit of control information. during the interval in which an area, of the moving web is adjacent one, of the character applying members.

During each printinginterval each unit of data informationis compared with a unit of control information in a single coincidence circuit and upon the detectionof an identity the coincidence circuit produces an output volt age pulse. Since a comparisonof all the information is accomplished by a single coincidence circuit, an output voltage from the circuit indicates that an identity exists between one oftheunitsof control and data information but taken alone it does not indicate which character applying member should be actuated. However, since the.

first delay line which carries the control information has a fixed time delay each unit of control information has a specific time relationship with respect to the beginning of each printing interval; that is, each unit has a fixed location in time. Therefore, the time at which an output pulse occurs after the beginning of a printing interval determines the character applying member which is to be actuated. In order to direct the output pulse of the coincidence circuit to the actuating mechanism for the selected character applying member, there is provided a distribution generator and a plurality of coincidence gates, one for each character applying member. The distribution generator is provided with a plurality of outputs leads, each lead being connected to a different coincidence gate. The output voltage from the single coincidence gate is applied in parallel to an input lead of each coincidence gate. Thedistribution generator applies an output voltage signal sequentially to each output lead, the application of the voltage signal to each of the leads being synchronized with the presentation of each of the particular units of control information to the coincidence gate. Therefore, the appearance of a voltage signal on a particular lead from the distribution generator indicates that a predetermined unit of control information is being presented to the single coincidence gate at this time, one of the coincidence gates is energized and actuates the character printing member associated with that gate.

The system as thus far described provides for comparison of each unit of data information With only one unit of control information, and does not provide for the sequential comparison of each unit of data information with each unit of control information. Sequential comparison of the units of data information with the units of control information is accomplished by inserting a third delay line in the recirculation loop of the first delay line which contains the control information. The delay time of the third delay is chosen such that the units of data information are shifted one unit of control information during each printing interval. Therefore, the units of data information are sequentially presented to the units of control information and a complete sensing mecha nism is provided.

It is, therefore, another object of the present invention to provide a high speed typewriter for printing on a continuously moving web of character receiving material employing a sensing mechanism utilizing delay lines for sequentially presenting to a coincidence circuit a plurality of units of data and control information in the form of voltage pulses.

Still another object of the present invention is to provide a printing mechanism for printing characters on a continuously moving web of print receiving material by means of a plurality of character printing members arranged in a row parallel to the direction of movement of the Web, and wherein actuation of the character printing members is controlled by a sensing mechanism employing delay lines for sequentially presenting units of control and data information to a coincidence circuit, and wherein an output voltage from the coincidence circuit indicating identity betweeen a unit of data and a unit of control information is gated to the proper character printing member through a plurality of coincidence gates sequentially gated by means of voltage pulses from a distribution generator.

The above and still further features, objects, and advantages of the invention will become apparent upon consideration of the following detailed description of specific embodiment of the invention, especially when taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a top view of the printing mechanism of the present invention and a partial schematic block.

diagram of the electrical components of a sensing mechanism incorporated in the present invention;

Figure 2 is a view of the present invention taken along the line 2-2 of Figure 1;

Figure 3 is a circuit diagram in block form of an embodiment of the present invention employing delay lines for sequential comparison of data and control information; and

Figure 4 is a timing diagram illustrating the timing of events in the circuit of Figure 3.

Referring to Figures 1 and 2 of the accompanying drawings, there is provided a printing mechanism having a flat, rectangular base member 1 which provides a support for the printing mechanism of the present invention. A first fiat rectangular plate 2 is positioned above and parallel to the base member 1 and is supported by a plurality of vertical legs 3 which rest upon the base member 1. The longitudinal inner edge of the plate 2 is provided with a vertical flange 4 to which is secured a first longitudinal edge of a rectangular platen 6. The other longitudinal edge of the platen 6 is secured to a vertical flange 7 provided on the longitudinal inner edge of a second flat rectangular plate 8. The rectangular plate 8 is positioned above and parallel to the base mem' ber 1 and is supported on a plurality of vertical legs 9 which rest upon the base member 1. The flat plates 2 and 8 have approximately the same longitudinal dimension and are transversely aligned.

Secured to the upper surface of the plate 2 are a plurality of solenoids 11 arranged in a row parallel to the flange 4, and, therefore, to the longitudinal dimension of the printing mechanism. Each of the solenoids 11 has a vertically reciprocal core 12 the upper end of each being secured to one of a plurality of type bars 13. Each of the type bars 13 extends transversely of the mechanism and terminates in a type member 14 positioned above and parallel to the platen 6. The type bars 13 are pivotally secured to a suitably mounted, longitudinally-extending shaft 16 to provide for vertical movement of the type members 14 in response to vertical movement of the cores 12 of the solenoids 11.

A second plurality of solenoids 17 are mounted on the top surface of the plate 8 and are arranged in a row parallel to the flange 7. Vertically reciprocal cores 18 of the solenoids 17 are secured to transverse type bars 19 which terminate in type members 21 positioned above and parallel to the platen 6. The type bars 19 are pivotally secured to a longitudinal shaft 22. The type members 14 and 21 are arranged in a row parallel to the longitudinal dimension of the platen 6, the type members 14 and 21 being alternately disposed in the row. A single row of solenoids, either 11 or 17, may be employed in place of the double row illustrated and described. The double row arrangement is preferable, however, since it requires less longitudinal space than a single row arrangement.

A web of printing receiving material 23, preferably paper, is fed from a feed roll 24, disposed at one end of the platen 6 and plates 2 and 8, to take-up roll 26 disposed at the other end of the platen 6. The web 23 extends parallel to the length of the platen 6 and is positioned between the platen 6 and the type members 14 and 21. The feed roll 24 is rotatably mounted on a shaft 27 which is suitably supported from the base 1. The take-up roll 26 is mounted on a shaft 28 which is supported in bearings for rotation about its axis.

The web 23 passes between two drive rollers 29, one being positioned above the other and only the upper one being illustrated. The rollers 29 are positioned between the take-up roll 26 and the end of the platen 6,. The web 23 is squeezed between the rollers 29, linear movement being imparted to the web 23 as a result of rotation of one or both of the rollers 29. The rollers 29 are secured to rotatably mounted shafts 31, the shaft 31 associated with the upper roller 29 being driven by a motor 32 through a gear box 33. The shaft 28 on which the take up'-roll is monnted,- is driven from the shaft 31 through a slip coupling 34.- Thedrive roll and take-uproll driv ing -arrangement-isemployed to'insure that the web 23 proceeds through the printing mechanism at a constant velocity eventhough the-peripheral velocity of the outer layer of the web on-the-roll 26 decreasesas the diameter of'the roll on theWeb on the take-up roll 26 increases.

The printing mechanism is provided with a longitudinally-extending endless ribbon 35' looped around the longitudinal dimension of the platen 6. The-portion of the ribbon above the platen 6 is disposed between the platen 6 and the Web- 23. The ribbon 35-passes over rollers 36"- and 37 disposed at opposite ends of the platen 6 betweentheends of the platen and the-feed and takeup-rollers 24' and 26. The roller 361s driven-by a rotatable shaft 38 towhich the roller 36 is secured. The shaft 334s suitably'mounted in bearings and is driven by the motor 32. The web 23 and ribbon 35 are driven at substantially the same speed by the drive roller 29 and the roller 36, rsepectively, to prevent'ink from being rubbed off on-theweb 23 as a result of relative motion between the web 23' and the ribbon 35.

The apparatus thus far described-is suitable for applying characters to the continuously moving web 23 in rcsponse to energi'zation of the-solenoids 11 and/ or 17. In operation of the printing mechanism, the motor 32 is energized and rotates the drive roller 29 and the takeup roll 26 and the roller 36. As a result, the web 23 and ribbon 35 --movc from right to left in the illustration of Figure 1. When one or more of the solenoids 11 is energized the core 12 associated with the energized solenoid moves upwardlycausing the associated type bar 13 to rotate clockwise; The type member 14 moves downwardly and the web 23 and ribbon 35 are pressed together between the type member 14 and the platen 6 and ink'is transferred from the ribbon 35 to the web 23 in accordance with the character to be applied to the web; The character to be applied to the web 23 may be formed on either the type member 14 or the platen 6, both arrangements being equally applicable to the present invention. The internal during which the web 23 and ribbon-35am pressed between the platen 6 and type member 14' is-relatively short compared with the velocity of the web 23 and ribbon 35 so that the movement of these latter two members is unimpeded.

The description of the operation of the solenoids 11, and type bars 13 for printing on the web 23 is equally applicable to the operation of the solenoids 1'7 and the type bars21.

In the embodiment. of the invention illustrated in Figures 1 and 2 of the accompanying drawings energization of the solenoids 11 and 17 and, therefore, actuationof the type bars 13 and 19 is under the control of aperf'o'rated tape sensing mechanism generally indicated at 39; A. perforated tape 41" is positioned above and parallel to the plate 8 and extends parallel to the flange 7' and, therefore, parallel-to the web 23. Transversely thetape 41 ispositioned between the outer edge of the plate 'and the row of solenoids 17; The tape 41 is supplied from a tape-feed roll 42 rotatably mounted on the shaft 27" to which the web feed roll 24 is also rotatably secured; The tape 41 is taken up on a tape take-up roll 43 secured to-a rotatable shaft 44 which may be axially aligned with theshaft 28-on which the web take-up roll 26 is mounted. Theshaft 44 is suitably supported in bearings for rotation about its axis. The tape 41 passes between two drive rollers 46, one being positioned above the other and only. the upper one being illustrated. The drive rollers 46"are longitudinally positioned between the take-uproll '43 and the end of the plate 8. The drive rollers 46-are secured to rotatable shafts 47, the upper one "of which" is d'rivenby the motor 32 through a gear box 483 The take-up roll 43 is driven through a slip coupling 49am :theshaft 47.

- Theperforated' tape 41 is perforated in accordance'witli' H in vertical alignment in the columns.

a three-out-of-nine code; that -is, each" transverse 1 column of the perforated tape 41 is provided with three perforations 51 which may be arranged in nine different locations in the column. The three-out-of-nine code provideseighty-four different arrangements of the three perfora tions in a'single column of the tape 41. The number eighty-four corresponds to the total number of type bars 13 and 17 which must be employed to provide all the characters carried on a standardtypewriter. The-stand ard typewriter employs only 42 type bars to provide 84 characters since each type-bar may supply two-characters as a result of the use of a shift mechanism. The printing mechanism of the present invention is not provided with a shift mechanism, and, therefore, requires 84' type bars.

The portion of the plate 8 disposed below'the'perforated' tape 41 is provided with perforations 52 arranged in columns of six parallel to the'columns of perforations in thetape 41. The arrangement of the six perforations 52 in each column is different from the arrangement of the perforations 52 in each of the other columns. Therefore, there are eighty-four different arrangements of perforations 52, each arrangement being indicative of one of the characters which may be applied-to the web 23. The spacings between columns of perforations and between the individual perforations in each column of theplate 8- are identical with the spacing of the columns and perfora tions, respectively, on the tape 41 so that a registration of the codes in the vertical plane is obtained. The'six perforations 52 in each column of the plate 8 are arranged to be complementary to the three perforations 51 in each column on the tape 41, and,- therefore, an identity between the information in a column of perforations 51 in the tape 41 and a column of perforations 52 in a column on the plate 8 is indicated when there are no perforations The longitudinal spacing between each column of perforations 51 and 52 on the tape 41 and plate 8, respectively, is taken to be the same as the spacing betweenthe type members 14 and 21, for the purposes of explanation only, and, therefore, the tape 41 is driven at the same velocity as the web 23 so" that a given columnof perforations 51 is presented to each column of perforations 52 on the plate 8 in synchronism with the presentation of a given area on the web 23' to each type member 14 and 21.

Positioned below each column of perforations 52 in the plate 8 is a photoelectric cell 53, only three of which areillustrated in Figure l, for sensing identity between the units of data and control information disposed on the tape 41 and the plate 8, respectively. Each photoelectric cell 53 is arranged in a light-tight compartment 54 situated under and secured to the bottom of the plate 8. Each compartment 54 is provided with two vertical side walls 56 defining the longitudinal limits of each compartment 54 andtwo vertical end walls 57, common to all of the compartments, defining the transverse limits of the compartments 54. A bottom wall 58 is disposed below all of the compartments and is joined to the walls 56 and 57.

Disposed above the tape-41 along the entire longitudinal dimension of the plate 8 is a light-tight compartment 59 in which is arranged one or more light bulbs 61 which provide light for the tape sensing apparatus. Light is directed downwardly first through the perforations 51 in thetape 41, then through the perforations 52 onithe plate 8 and then to the photocells 53.

Each photocell is connected through a separate phase inversionamplifier 62 to one input terminal 63 of a coincidence gate 64. Another input terminal 66 ofieachco'incidence gate 64 is connected over a common lead 67 to a stationary contact 68 of a make-and-break switch 69. A movable contact 71 of the switch 69 is connected'to a source of D. C. voltage 72. The movable contact 71 of the switch 69. isspring biased to engagethe'circumference of a cam 73 having a raised portion 74. The cam' 73 is' se'cured toa shaft 76' which is driven by'the' m'otor 32 through'a gear box 77. Rotation of thecam 73 is synchronized with the movement of the tape 41 so that the portion 74 of the cam 73 raises the contact 71 into engagement with the contact 69 only during the intervals when a row of perforations 51 on the tape 41 is disposed above a row of perforations 52 in the plate 8. Closing of the switch 69 applies a voltage pulse to each of the coincidence gates 64.

An output lead 78 of each coincidence gate 64 is connected to a separate solenoid 11 or 17. In Figure 1, the left-hand coincidence gate 64 is provided with an output lead 78 marked a, which is connected to the solenoid 11 having an input lead marked a. The coincidence gate output lead 78 which is designated by the letter b is connected to the solenoid 17 having an input lead designated by the letter b. The remainder of the coincidence gates 64 and the solenoids 11 and 17 are similarly interconnected.

In operation of the sensing mechanism 39, the tape 41 moves from right to left as a result of rotation of the upper feed roller 46 by the motor 32. Each column of perforations 51 on the tape 41, is sequentially presented to each column of perforations 52 in the plate 8, as the tape 41 is moved. Complementary codes are employed for the data and control information and, therefore, when an identity occurs between these two codes; that is, when a unit of data information indicating that a particular character is to be printed is presented to a unit of control information representing that character, none of the perforations 51 are in vertical alignment with any of the perforations 52 and no light from the source 61 can reach the photoelectric cell 53 disposed below these columns. When this occurs there is no output voltage from the photoelectric cell 53 to its associated phase inverter amplifier 62. As a result, the output voltage from the amplifier 62 is high and a voltage appears at the input 63 of the associated coincidence gate 64. This voltage is gated by a voltage pulse on the lead 67 which is generated periodically by the switch 69, cam 74, and battery 72. The voltage gated through the coincidence gate 64 appears on its output lead 78 and is connected over this lead to one of the solenoids 11 or 17. The selected solenoid is energized and rotates its associated type bar 13 or 19 thereby causing a character to be applied to the web 23.

Since the tape 41 and web 23 proceed through the printing mechanism at the same speed, each area of the web 23, that is to receive a character, is transversely aligned with a column of perforations 51 on the tape 41. As this column of perforations 51 is sequentially presented to each of the columns of perforations 52 in the plate, the transversely aligned area of the web 23 is sequentially presented to the type members 14 and 21 represented by the perforations 52 to which the column of perforations 51 is presented. When a column of perforations 51 is presented to a column of perforations 52, which is arranged complementary thereto, the transversely aligned area of the web 23 is adjacent the one type member 14 or 21 represented by the column of perforations 51 under discussion and the desired character is applied to that area.

The arrangement of the sensing mechanism 39 as illustrated in Figures 1 and 2 was chosen so as tosimplify the explanation of the operation of the device. However, this arrangement is merely exemplary and numerous other arrangements may be used. Thus the sensing mechanism 39 may be physically separate from the printing mechanism so long as the drive mechanisms of the web 23 and the tape 41 are synchronized.

The synchronizing mechanism provided by the battery 72, switch 69, the cam 73 is necessary to prevent false actuation of the solenoids 11 and 17 during those intervals when a portion of the tape 41 situated between columns of perforations 51 and, therefore, having no perforations, is disposed above a column of perforations 52. Since no light can reach any of the photoelectric cells 53 during these intervals the coincidence gate 64 must be blocked to prevent false actuation of all of thesolenoids 11 and 17. The synchronizing system may take a different form from that described and illustrated. Thus one extra photocell arranged below a tenth row of perforations on the tape would also serve this purpose.

In the embodiment of the invention illustrated in Figures 1 and 2 the units of data and control information have a physical representation in the sensing mechanism 39; that is they are represented by the columns of perforations 51 and 52, respectively. The present invention is not limited to a physical representation of the units of data and control information in the sensing mechanism and in the embodiment of the invention illustrated in Figure 3 they are represented by coded voltage pulses. The arrangement of the mechanism for applying characters to the web 23 is the same in the embodiment of Figure 3 as in the embodiment of Figure 1 and, therefore, only the sensing mechanism is illustrated in Figure 3.

Referring to Figure 3 there is provided a first delay line 81 which contains voltage pulses representing the units of control information. The time delay of the delay line 81 is equal to of the period during which an area on the web 23 is adjacent eachtype member 14 or 21. The time interval assigned to each unit of control information is such that the delay line 81 may store eightly-four of these units at a time. If a three-out-ofnine code is to be employed to represent the units of control information, the frequency of the voltage pulses representing the units of control information must be such that nine voltage pulses may occur serially during each time interval. Only three voltage pulses are generated during each interval and the arrangement of these three pulses in the nine different time locations determines the code in that interval. A three-out-of-nine code is again employed since it provides 84 different arrangements of the three pulses in the nine time locations.

An output lead 82 of the delay line 81 is connected to a first input terminal 83 of a coincidence detector 84 and also over lead 86, and through a second delay line 87, a buffer 88 synchronizing gate 126 and a driver amplifier 89 to an input lead 91 of the first delay line 81; the elements 86, 87, 88, 126, 89, and 91 constituting a recirculation circuit 92 of the delay line 81.

The delay time of the first delay line 81 is sufficiently long for the delay line 81 to accommodate eighty-four units of control information While the delay time of the second delay line 87 is equal to the time interval required for one unit of control information. The combined delay of the delay lines 81 and 87 is equal, therefore, to eighty-five time intervals and since only eighty-four units of control information are applied to the delay line 81, there is one interval during which no control information appears thereon.

The buffer 83 is provided with an input lead 93 over which the voltage pulses representing the units of control information are initially applied to the system. Voltage pulses applied to the lead 93 pass through the bufier 88, are synchronized by gate 126, amplified by the driver amplifier 89, and applied to the delay line 81 over the lead 91. The pulses proceed through the delay line 81 and subsequently appear on the output lead 82. The pulses appearing on the output lead 82 are presented to the coincidence circuit 84 and are also reapplied to the input lead 91 of the delay line 81 through the circulating circuit 92. Once all of the units of control information have been applied to the delay line 81, the delay line 81 and the recirculation circuit 91 store the information indefinitely and, therefore, provide a memory device for the control information.

A third delay line 94 is provided for storing voltage pulses representing the units of data information. The delay line 94 is provided with an input lead 96 and an output lead 97 which is connected to a second input terminal 98 of the coincidence device 84. The voltage pulsesiappearingaon the output lead97 are also connected over a lea'd 99 and through a recirculation circuitltll], comprising coincidencegate 11H, abuffer 102, a synchronizing gate 127 anda driver amplifier lui'a'connectedin series, to the input lead 96 of the delay line 94.

A. predetermined time interval is assigned to each unit of data information, the. interval being the same as the interval assigned to each unit of control information. The voltage pulses representing the units of data information are also coded in accordance with three-out-ofnine code so that each unit of data information is representedby three voltage pulses having eightly-four different arrangements in the nine different pulse times per interval.

Since eachunit of datainformation is representative ofIaparticular character to be applied to the web 23, each unit must be first inserted in the delay line 94, sequentially, compared with all of the units of control informationand then discarded and a new unit of data information inserted in its place. To accomplish these operations there is provided'a stable oscillator 104, which generates a voltage pulse whenever a pulse for representing data and control information may occur. These pulses are applied to a distributor generator 131, which is a ringzcounter having nine stages. An output lead from each of these stages is applied to a different lead 181 connected to a different coincidence gate 133. Information. to be inserted into the system is represented by signals on three of the nine leads 132 of the gates 133. Since the leads 131 contain voltage signals successively, the three voltage'signals on leads 132 cause pulses during three of the nine time locations of each time interval to pass through a buffer 135 to output lead 124.

- Every ninth pulse applied to the distributor generator 131 causes a pulse to be applied to a distributor generator 112 which contains a counter having eighty-five stages, eighty-four of these stages being each connected with a different output lead 113. Each of eight-four of the output leads 113 is connected to an input terminal 114 of a different coincidence gate 116 only three of which are illustrated in Figure 3. A second input terminal 117 of all of the coincidence gates 11s are connected in parallel to an output terminal 118 of the coincidence circuit 84. An output terminal 120 of each of the coincidence gates 116 is connected to a different one of the solenoids 11 and 17 illustrated in Figure l. ince a single coincidence circuit'84is employed to detect identity between all of the units of data and control information, it is necessary to employ the distributor generator 112 to insure that an output voltage from the coincidence circuit 84 energizes the proper solenoid'll or 17. Since the delay of the delay lines 81 and 87 remains substantially constant, the time of appearance of each unit of control information at the input terminal 83 of the coincidence circuit 84 is fixed in time; that is, has a predetermined location in time. The distributor generator 112 is timed by the oscillator 104 to open the coincidence gate 116 which controls printing of the character represented by the unit of control information appearing at the input terminal 83 of the coincidence circuit 84 simultaneously with the appearance of that unit of control information on the input terminal 83. Since the delay lines 81 and 87 provide eight-five intervals of delay, the distributor generator 112 must contain eightfive stages in the ring counter so as to remain in synchronismwith the control information. However, since there areonly eighty-four units of control information, only eighty-four stages ofv the distributor generator 112 are connected to control coincidence gates 116. The eightyfi fthoutput lead' 113 from the distributor generator 112 is unconnected.

The first stage of the distributor generator 112 is connectedthrough lead 119 and a phase inverter. amplifier 121-to a second input terminal 111 of the coincidence gate 101. The lead 119 is also-connected to a first input terminal 122 of a coincidence gate 123 provided with a sec ondinput'fromlead 124'. Thevoltage'p'ulses appearing on the: lead 1'19. control the? gating: of new data information intothe' delay line 94and block the recirculation loop 100- of the: delay-line 94during the intervals in which new data information is being gated in.

Voltage pulses representing new units of datainforma-- tion are applied,.as was described previously, to the lead 124 to the coincidence gate 123 and are gated through the gate123' by: the pulses from the lead 113' connected to the first stage of the distributor generator 112. Therefore, anew unit ofdatainformation may be added to the delay is one interval of delay between the input and output of the delay line 81 provided by delay line 87, thisis. the interval during which no unit of control information is applied=to the input-of the delay'line 81.

During this'interva'l the pulse appearing on thelead119 blocks the recirculation circuit 100 of the delay line'94-and gateouta unit of information which is being compared in the coincidence circuit 84 withthelast of eighty-four units ofcontrol information. pulse is applied to the lead 1-19the output voltage from the amp'lifier 121 is high and the coincidence gate 101 is openand passes pulses appearing on the output lead 97 of the delay'line- 94--throughthe coincidence gate 101, and, therefore; through the recirculation circuit 100 to the input lead 96 of the'delay line 94. When a pulse appears on the. lead 119the output voltage of the amplifier 121 falls and blocks the coincidence gate'101. Therefore, during the interval. that a new unit ofdata information is gated through the gate 123, the voltage pulses appearing at the outputof the delay line 94 are blocked in the circulation loop 100 and disappear from the system.

Tacompensate for errors in the delays of circuits 92 and 100, these'circuits are designed so that information pulses appearing at terminals 138 and 139 will enable synchronized pulses from oscillator 104 to terminals 136 and 137 respectively to pass through coincidence gates 126 and 127" respectively to'driver amplifiers 89 and 103 respectively.

Beforeany units of data information are inserted into recirculation circuit 100, it is necessary to fill recirculation circuit 92 with 84-units of control information. These units of control information are inserted through gate 123 into recirculation-circuit 100 in the same manner as units of data information. When all eighty-four units of control information have been inserted into circuit 180, a signal'on lea'd 130 will enable the control information to'pass through lead 129, gate 128 and lead 93 and buffer 88 into recirculation circuit 92. The enabling signal is then removed from lead 131).

The operation of the circuit of Figure 3 is explained with reference to the timing graphs of Figure 4. Graphs A and. B are timing diagrams illustrating when each unit of control information appears on the leads 82 and 91, respectively. Graphs C and D-are timing diagrams illustrating when eachunit of data information appears on the leads 96 and 97, respectively, and Graph E illustrates the time of. appearance of pulses on the lead 119. The timing diagrams are arranged in groups of five cycles of operation, each cycle of operation corresponding to the combined delay time of thedelay lines 81 and 87; that is, eighty-five time intervals. The cycles represented in Figure 4 are the first to third and 84 and 85 cycles. Only four time intervals of each cycle are represented in the graphs, they being the first and second and eighty-fourth and eighty-fifth intervals. The first of the eighty-five intervals appearing on the output lead 82 of the delay line 81 is arbitrarily chosen for the purposes of explanation as the interval occurring immediately after the interval in which no control information is carried'by the delay line 81, the latter interval being designated as the eightyfifth inte'rv'al. Since there isone interval of delaybetwe'en During those periods when nothe lead 82 and the lead 91 provided by the delay line 87, the eighty-fifth interval appears on the lead 91 at the same time the first interval appears on the lead 82. The relationship between the intervals appearing on the leads 82 and 91 is fixed and, therefore, remains the same during all cycles of operation.

At the time that the first interval appears on lead 82, a pulse is applied to the lead 113 of the distributor generator 112, which is connected to the lead 119. This pulse gates a first unit of new data information through the coincidence gate 123 so that the first new unit of data in formation appears on the input lead 96 of the delay line 94 at the same time that the eighty-fifth interval appears on the input lead 91 of the delay line 81. Since the time of delay in the delay lines 81 and 94 is the same, the first unit of information and the eighty-fifth interval of the delay line 81 appear on the output leads 82 and 97 at the same time after a delay of eighty-four time intervals. Since the eighty-fifth interval associated with the delay line 31 contains no control information there can be no output from the coincidence circuit 84 at this time.

The first unit of data information appearing on the lead 97 is gated through the coincidence gate 101 since no voltage pulse appears on lead 119. As there is no time delay between the pulses appearing on the leads 97 and 96, this first unit of data information appears on the lead 96 at the same time that it appears on the lead 9'7. Since there is one interval of delay between the output lead 82 and the input lead 91 of the delay line 81, the eighty-fourth unit of control information appears on the lead 91 at the same time that the first unit of data information appears on the lead 96, during the last interval of the first cycle. Therefore, the data information is advanced one interval with respect to the control information.

During the first interval of the second cycle of operation a second unit of data information is gated to the lead 96 as a result of a pulse appearing on the lead 119. The second unit immediately follows in time the first unit of data information and both proceed through the delay line 94. At the end of eighty-four time intervals the first unit of data information is compared with the eightyfourth unit of control information and if an identity is detected by the coincidence circuit 84, an output voltage appears at the terminal 118. This voltage is gated through the coincidence gate 116 associated with the eighty-fourth lead of the distributor generator 112 and actuates the associated solenoid 11 or 17 to cause a character to be printed on the web 23.

The first unit of data information is gated through the coincidence gate 101 since no pulse appears on lead 119 at this time and is again advanced one interval with respect to the control information as a result of the delay line 37 and, therefore, appears on the lead 96 at the same time that the eighty-third unit of control information appears on the lead 91. During the next interval the second unit of data appears on the lead 97 at the same time as the eighty-fifth interval on the lead 82 and also appears on the lead 96 at the same time that the eightyfourth interval appears on the lead 91.

During each of the subsequent cycles of operation each of the units of data information is advanced one interval with respect to the control information until compared with all of the units of control information. During the first interval of the eighty-fourth cycle of operation, the first unit of data information appears on the lead 97 at the same time that the first unit of control information appears on the lead 82. Therefore, the first unit of data information has now been compared with all eighty-four of the units of control information and can now be discarded. As previously pointed out, a pulse appears on the lead 119 during the first interval of each cycle and blocks the coincidence gate 101. As a result, the first unit of data information does not appear on the input lead 96 and in its placean eighty-fifth unit of data information is gated through the coincidence 123 to the lead 96. During the eighty-fifth cycle of operation the second unit of data information is compared with the first unit of control information and the eighty-sixth unit of data information is inserted in its place on lead 96.

Synchronization of the operation of the circuit of Figure 3 with the travel of the web 23 through the printing mechanism illustrated in Figures 1 and 2 is accomplished by choosing the time delay of each of the delay lines 81 and 94 equal to a period during which an area of the web is positioned adjacent each character printing member. The oscillator 104 may also be synchronized with the progression of the web 23 through the printing mechanism by applying the voltage pulses appearing on the lead 67 of Figure l to the oscillator 104 as synchronizing pulses for the oscillator 104.

The coincidence gates 101, 116, 123, 126, 127, 128 and 133; the buffers 88, 102 and 135; the amplifiers 89, 103, and 121; the oscillator 104; the coincidence circuit 84; the distributor generator 112 and the counter 131 are all illustrated in block form in Figure 3 since each of these elements is well known in the art and the invention is not concerned with the specific circuitry of these elements.

In the embodiment of the invention illustrated in Figure 3, single delay lines 81, 87, and 94 are employed to store the control and data information respectively and the units of control and data information are represented by three voltage pulses applied in series to the delay lines 81 and 94. A system employing nine delay lines 81, nine delay lines 87 and nine delay lines 94 may equally well be employed. In such an arrangement the three voltage pulses representing a unit of information would be applied in parallel to any three of the nine delay lines. The selection of the three delay lines energized during any interval determines the code applied. The coincidence circuit 84 would be a parallel coincidence circuit. Outside of these changes and the utilization of nine parallel recirculation circuits 92 and 100 the system of Figure 3 may remain the same, and the operation of the system remains as previously described.

Also, in the embodiment of the invention illustrated in Figure 3, electrical delay lines were used. It is obvious that mercury delay lines, quartz crystal delay lines or other means for storing digital information so that it would be available after a predetermined delay could be used instead of electrical delay lines 81, 87, and 94. Furthermore, the eighty-five time intervals of delay from the combination of 'delay lines 81 and 87 would be obtained from a single delay line. It would also be possible to change the delays in recirculation circuits 92 and 100 without departing from the spirit of this invention. For example, it would be possible to change recirculation circuit 92 to have a delay of 84 time intervals and recirculation circuit 100 to have a delay of time intervals, provided that the oscillator 104 and the distributor generator 112 were modified so that the distributor generator passed through 84 instead of 85 stages within the period during which an area on the web 23 is adjacent to each type 14 or 21.

While I have described and illustrated one specific embodiment of the present invention, it will be clear that variations of the specific details of construction may be resorted to without departing from the true spirit of the invention as defined in the appended claims.

What I claim is:

1. In combination, a plurality of printing means arranged in a row, first feed means for continuously moving a web of print receiving material parallel to said row of printing means, said printing means being arranged to apply characters to selected areas of said web, control means for selectively energizing said printing means, said control means comprising means for representing each of said printing means by a different unit of coded control information, means for representing each character to be applied to said Web by a unit of coded data information,

ofdata information to each unit of control information,

means for synchronizing said second feed means with said first feed means so that the area of said web that is to receive a particular character is presented to the printing means for printing said particular character simultaneously with the presentation of the unit of data information to the unit of control information, each representing said particular character, comparison means for detecting identity between units of data and control information and for producing an indication of such an identity and actuating means responsive to said indication for energizing the printing means represented by said data information.

2. The combination in accordance with claim 1, wherein said means for representing said units of data information and control information are first and second opaque members, respectively, each having a plurality of transparent areas arranged in columns, each column of transparent areas representing one unit of information, said feed means sequentially aligning each column of transparent areas on said first opaque member with each column of transparent areas on said second opaque member.

3. The combination in accordance with claim 2, wherein the arrangement of transparent areas in a column on said first opaque member for representing a particular printing means is complementary to the arrangement of transparent areas in a column on said second opaque member representing said particular printing means, and wherein said means for detecting an identity between said units of data and control information is a photoelectric means for detecting when light does not pass through aligned columns of both of said opaque members.

4. The combination in accordance with claim 3, wherein there is provided synchronizing means for rendering said photoelectric means operative only when a column of transparent areas on said first opaque member is aligned with a column of transparent areas on said second opaque member.

5. The combination in accordance with claim 1, wherein each unit of control information is represented by a first plurality of discrete indicators, a first information storage medium for storing a plurality of units of control information, each unit of control information being assigned a predetermined location in said information storage medium, the arrangement of said discrete indicators in each of said locations determining the control information stored in each location, and wherein each unit of data information is represented by a second plurality of discrete indicators, a second information storage medium r for storing a plurality of units of data information, each unit of data information having a predetermined location in said second information storage medium, the arrangement of said second plurality of discrete indicators in each of said locations determining the data information stored in each location.

6. The combination in accordance with claim 5, wherein said first information storage medium comprises a first delay line having a recirculation loop, a second delay line connected in said recirculation loop, said first delay line having a delay time sufficient to store a number of units of control information equal to the number of printing means, said second delay line having a delay time sufficient to store one unit of control information, each of said units being assigned a predetermined time location in said first delay line, and wherein said second information storage medium comprises a third delay line having a recirculation loop, said third delay line having a delay time equal to the delay time of said first delay line, and wherein the discrete indicators for each of said units of control and data information are signal pulses.

7. T hecombination in accordance with claim 6, wherein. said means for detecting identity between units of data: and control information comprises a coincidence ,means for detecting an identity of arrangement ofsaid 16 signal pulses in-each of said-time; locationsandfor producing an output signal upon detection of an identity.

8. The combination in accordancewith claim 7, wherein said actuating means comprises a plurality of coincidence means equal in number to said printingmeans, each of said coincidence gating means having at least two input terminals, one of said input-terminals-of each of said coincidencegating means being connected'toreceive an output signal from said coincidence means, a distributor means having a number of output leads equal to one more than the number of said printing means, said distributor means sequentially applying an output voltage to each of said output leads, each of said output leads being connected to second input terminal of' a different coincidence gating means, thereby leaving one of said output leads unconnected.

9. The combination in accordance with claim 8, wherein there is provided an oscillator means for sequencing said distributor means, a gating.circuit connected in said recirculation loop of said third delay line for controlling the flow of units of data information through said recirculation loop, means responsive to said oscillator means for periodically opening said gating circuit to allow recirculation through said recirculation loop, and means responsive to a voltage pulse appearing on one of said output leads from said distributor means for closing said gating circuit, gatingv means for applying new units of data information to said third delay line and means responsive to a voltage pulse on said one of said output leads for opening said gating means.

10. In a printing mechanism employing a plurality of printing means arranged in arow for printing on a web of print receiving material moving parallelto said row of printing means, sensing means comprising a plurality of units of control information, each unit of control information being assigned apredetermined unitlocation, and being represented by six discrete indicators arranged in six of nine different indicator locations within each unit location, a plurality of units of data information, each assigned a predetermined unit location and being represented by three discrete indicators arranged in three of nine different indicator locations within each unit location.

11. The combination in accordance with claim 5 wherein said first information storage medium comprises a first delay line circuit including a recirculation loop, said delay line circuit having a total delay timeequal to a time sufficient to store a number of units of control information equal to one more than the number of printing means, each of said units being assigned a predetermined time location in said delay line, and wherein said second information storage medium comprises a second delay line circuit including a recirculating loop, said second delay line circuit having a delay time sufiicient to store a number of units of data information equal to the number of printing means and wherein the discrete indicators for each of said units of control and data information are signal pulses.

12. The combination in accordance with claim ll, wherein said means for detecting identity between units of data and control information comprises a coincidence means for detecting an identity of arrangement of said pulses in each of said time locations and for producing an output signal upon detection of an identity.

13. The combination in accordance with claim 12, wherein said actuating means comprises a plurality of coincidence gating means equal in number to said printing means each of said coincidence gating means having at least two input terminals, one of said input terminals of each of said coincidence gating means being connected to receive an output from said coincidence means, a distributor means having a number of output leads equal to one more than the number of said printing means. said distributor means sequentially applying an output voltage to each of said outputv leads, each of said output leads 17 being connected to a second input terminal of a difierent coincidence gating means.

14. The combination in accordance with claim 13, wherein there is provided an oscillator means for sequencing said distributor means, a gating circuit connected in said recirculation loop of said second delay line for controlling the fiow of units of data information through said recirculation loop, means responsive to said oscillator means for periodically opening said gating circuit to allow recirculation of signal pulses through said recirculation loop, and means responsive to a voltage pulse appearing on one of said output leads from said distributor means for closing said gating circuit, gating means for applying new units of data information to said second delay line and means responsive to a voltage pulse on said one of said output leads for opening said gating means.

15. In combination, a plurality of printing means arranged in a row, first feed means for continuously moving a Web of print receiving material parallel to said row of printing means, said printing means being arranged to apply characters to selected areas of said web, control means for selectively energizing said printing means, said control means comprising means for representing each of said printing means by a difierent unit of coded control information, means for representing each character to be applied to said web by a unit of coded data information, second feed means for sequentially presenting each unit of data information to each unit of control information, means for synchronizing said second feed means with said first feed means so that the area of said web that is to receive a particular character is presented to the printing means for printing said particular character simultaneously with the presentation of the unit of data information to the unit of control information, each representing said particular character, comparison means for detecting identity between units of data and control information and for producing an indication of such an identity and actuating means responsive to said indication for energizing the printing means represented by said data information, said units of control and data information being represented by discrete indicators arranged in a complementary three out of nine code.

References Cited in the file of this patent UNITED STATES PATENTS 1,975,791 Hopkins Oct. 9, 1934 2,343,398 Bryce Mar. 7, 1944 2,461,451 Tholstrup Feb. 8, 1949 2,692,551 Potter Oct. 26, 1954 

